New species, new records and new morphological characters of the genus Tillicera Spinola from China (Coleoptera, Cleridae, Clerinae)

Abstract Two new species of the genus Tillicera Spinola, 1841 from China are described and illustrated: Tillicera sensibilis sp. n. from Yunnan (also from Myanmar, Thailand and Laos) and Tillicera wenii sp. n. from Taiwan. Tillicera bibalteata Gorham, 1892, Tillicera hirsuta (Pic, 1926) and Tillicera michaeli Gerstmeier & Bernhard, 2010 are newly recorded from China. Tillicera auratofasciata (Pic, 1927) is newly recorded in some provinces of China. A key to species of the genus from China is provided. Relationships between species are discussed with emphasis on characters of male phallus, female internal reproductive organs and pit-like sensilla in male terminal antennomere, which is discovered in Tillicera for the first time. The present generic definition of Tillicera is discussed as well. Photos of terminalia of the previously known species are also provided for comparison.


introduction
Fifteen species of the oriental genus Tillicera Spinola, 1841 were recognized by Gerstmeier and Bernhard (2010) whose thorough generic revision, with the exception of T. assamensis Stebbing, 1907 from Assam, India, was based on first hand examination of primary types. Two species occur in China: T. auratofasciata (Pic, 1927) from Xizang and T. cleroides Gorham, 1892 from Yunnan. In the course of our studies of material from several major Chinese collections and additionally some European museums, two new species were discovered: Tillicera sensibilis sp. n. from Yunnan (also from Myanmar, Thailand and Laos) and Tillicera wenii sp. n. from Taiwan; both of which exhibiting a similar habitus to that of T. auratofasciata (Pic, 1927), T. javana Spinola, 1844 and T. soror Schenkling, 1902, but with significantly different aedeagi. Furthermore, new distribution records of some previously known species were found. Gerstmeier and Bernhard (2010) did not separate the tegmen and phallus, and thus some systematically significant characters of the phallus were not quite clear. In the present study the tegmen and phallus are separated apart and fine structures of the phallus are carefully compared.
For the first time, high resolution color photographs of female internal reproductive organs of Cleridae are provided. The female internal reproductive organs of all the species from China are compared except for T. wenii due to a lack of specimens. And for the first time, pit-like sensilla on the male terminal antennomere in Tillicera is discovered (in dorsal view). Comparative photographs of this structure are presented for T. auratofasciata and the two new species described herein. The purpose of this paper is to describe two new species, present new distribution records for previously known species, discuss the relationships among species and the generic definition of the genus, and provide some new morphological characters which might better facilitate further systematic study of the genera related to Tillicera and Clerus.

Material and methods
Materials examined are deposited in the following collections; abbreviations as shown in the text:

NMPC
National Museum, Prague, Czech Republic RGCM Roland Gerstmeier Collection, Munich, Germany SHNU Department of Biology, Shanghai Normal University, China SWFU Southwest Forestry University, Kunming, China Whole male abdomens were removed from the body with fine forceps, treated with 10% KOH solution at room temperature for 8-12 hours. Terminalia were prized apart, rinsed and examined in 70% ethanol, then photographed in glycerol and eventually stored within glycerol in genital vials which were pinned below specimens. Female internal organs were all dissected from dry specimens. The female specimens of T. auratofasciata and T. sensibilis, collected in 2009 and 2008 respectively, were killed by ethyl acetate then preserved in ethanol and pinned later. Whole female abdomens were removed from the body with fine forceps, treated with 10% KOH solution at room temperature for 12-16 hours. Female reproductive organs were prized apart, rinsed in 70% ethanol, stained with chlorazol black E saturated solution in 70% ethanol for 40 seconds, photographed in 70% ethanol then mounted on a plastic slide in euparal, which was pinned below specimens. Antennae were removed from the head (segments 3-11 of T. auratofasciata and T. sensibilis; 10-11 of T. wenii), treated with 10% KOH solution at room temperature for 48 hours and rinsed with water before being photographed.
Habitus images were captured using a Canon 450D digital camera with Canon Macro 100 mm lens; genitalia were captured by a Canon 450D digital camera fitted to a Nikon SMZ-1500 stereoscopic dissecting microscope; antennae were captured by a Nikon digital Sight DS-SM camera fitted to a Nikon SMZ-1500 stereoscopic dissecting microscope controlled by ACT-2U software. Series of partially focused photographs were taken and then combined using Helicon Focus software, and finally processed with Adobe Photoshop software. Line drawings of pronota were made from color photographs with the software Adobe Illustrator.
Measurements were made under a stereo microscope using an ocular micrometer. Body length is the linear distance from labrum to elytral apex. Body width is the maximum width across elytra. Lengths and widths of terminal antennomeres were measured as in Fig. 29.
Terminology mostly accorded with Ekis (1977). When describing the phallus, we do not consider the natural orientation, but define the dorsal face as the position where the median orifice (sensu Sharp and Muir 1912) opens, (and the opposite as the ventral face), and thus, each phallic plate has a dorsal margin and a ventral margin, and the membrane connecting the two ventral margin called phallic ventral membrane. The pulvillus of tarsomeres is abbreviated to P; for example 'P1' indicates pulvillus of the tarsomere 1, and 'pro-P1' indicates the pulvillus of the protarsomere 1 (clerids usually have pulvilli present on tarsomeres 1-4, while tarsomere 5 is slender and without a pulvillus).
Terminal antennomere: Length to width ratio of both sexes below 1.5; male with a shallow pit-like sensillum present at basal third, diameter 0.08 mm (clearly distinct in magnification 100× before and after treated with KOH solution) (Figs 29, 32).
Male terminalia: Ratio of length of paramere to whole tegmen 0.17: 1, paramere thumb-like in dorsal view, dorsal sinus triangular, ventral sinus digitiform (Figs 5-6); phallic plate with large denticles along dorsal margin and fine granular structures on posterior sclerotized area (denticles extending from anterior half to posterior sclerotized area; number of denticles can vary between left and right phallic plate and between individuals but whole length of denticles is consistent) ( (Pic, 1927), Revision 2009, Gerstmeier & Bernhard" (MNHN).
Remarks. The name-bearing type was not fixed in the original publication and there was no imply how many type series was. For the purpose to fix the name-bearing type, the lectotype is designated here, which is the same specimen noted as "holotype" in Gerstmeier & Bernhard (2010).
Other material examined   Diagnosis. Distinguishable from superficially similar specimens of T. auratofasciata by body slender (length to width of elytra: male about 2.37, female 2.16), length to width ratio of terminal antennomere of both sexes equal to or above 1.5, metaepisternum and metasternum earth-yellow, pubescence on metaepisternum and metasternum white and distinctly thinner than light yellow decumbent setae on elytra, yellow setal pattern on elytral apical third much narrowing towards suture, dorsal and ventral sinuses of tegmen oblong, and dorsal margin of phallus with large denticles extending from apical third towards apex; and distinguishable from T. wenii by pattern-forming setae on elytra more gold colored, meta-P1 absent and meta-P2 just vestigeal (Figs 39,40), pit-like sensilla of male terminal antennomere larger and shallower [distinct in magnification 100x before treated with KOH solution] (Figs 30, 33), parameres parallel, with apex obtuse, dorsal and ventral sinuses oblong, and dorsal margin of phallus with large denticles extending from apical third towards apex.
Elytra: Length to width ratio: male average about 2.37, female average about 2.16; integument tricolored, basal third orange, posterior two-thirds black; with a pair of lateral yellow maculae before middle, each distance from lateral margin to two-thirds way towards suture, matted with golden yellow, decumbent setae; behind two maculae, with a central backward opened lunate band formed of yellow decumbent setae (sometimes with a pale integumental spot in middle); apical third with another pair of yellow maculae, spanning from lateral margin to, or nearly to, suture, matted with golden yellow, decumbent setae, setal pattern narrowing towards suture; basal third regularly and deeply punctate in rows, diameter of punctures larger than intervals; inner two rows of elytral punctation fading away behind lunate band; basal third with erect, black setae (extreme base with some yellow setae), black part with posteriorly directed, black, decumbent pubescence (apical third mixed with some yellow setae).
Abdomen: Black. Male terminalia: Ratio of length of paramere to whole tegmen 0.26: 1, parameres parallel, apex obtuse, dorsal and ventral sinuses both oblong, latter broader and deeper ; phallic plate with large denticles along dorsal margin and fine granular structures on posterior sclerotized area (denticles extending from anterior third to posterior sclerotized area; number of denticles may vary between left and right phallic plate and between individuals but whole length of denticles is consistent) (Figs 15-16, 20); phallic ventral membrane with one line of file-like structures on each side (Fig. 15); spicular fork (Fig. 17); tergum VIII ( Fig. 18), sternum VIII (Fig. 19).
Female reproductive organs: Vagina swollen, base of bursa copulatrix narrower than posterior end of vagina; length of bursa copulatrix three times as long as spermatheca; swollen zone between vagina and spermathecal duct smaller than that in T. sensibilis; spermathecal gland attached to basal fourth of spermatheca (Fig. 38); both dorsal and ventral lamina of ovipositor divided.
Distribution. China: Yunnan; Myanmar; Thailand; Laos. Etymology. The specific epithet sensibilis (= having the faculty of sensation) is a Latin adjective, referring to the presence of the pit-like sensillum in male terminal antennomere, which is first discovered in this species. Diagnosis. Distinguishable from superficially similar specimens of T. auratofasciata by pattern-forming setae on elytra paler, metasternum and metaepisternum earthyellow, pubescence on metaepisternum and metasternum white and distinctly thinner than light yellow decumbent setae on elytra, meta-P1 evident and meta-P2 bilobed (Figs 39-40), pit-like sensilla of male terminal antennomere oblique, smaller and deeper (indistinct in magnification 100x before treated with KOH solution) (Figs 29, 31), paramere pointed; and distinguishable from T. sensibilis by pattern-forming setae on elytra paler, meta-P1 evident and meta-P2 bilobed (Figs 39-40), pit-like sensilla of male terminal antennomere oblique, smaller and deeper (indistinct in magnification 100x before treated with KOH solution) (Figs 30-31, 33), paramere pointed, dorsal and ventral sinuses both lanceolate, and dorsal margin of phallus with large denticles extending from basal half towards apex.
Elytra: Length to width ratio: male average about 2.30, female unknown; integument tricolored, basal two-fifths orange, posterior three-fifths black; with a pair of light yellow maculae before middle, each spanning from lateral margin to two-thirds way towards suture, matted with greyish yellow, decumbent setae; behind two maculae, with a central backward opened lunate band formed of yellow decumbent setae, more or less joining with anterior maculae; apical third with another pair of light yellow maculae, spanning from lateral margin to, or nearly to, suture, matted with greyish yellow, decumbent setae, setal patterns broadly meeting at suture; basal two-fifths regularly and comparatively shallowly punctate in rows, diameter of punctures a little smaller than, or as wide as, intervals; inner four rows of elytral punctation fading away behind lunate band; basal two-fifths with erect, black setae (extreme base with some light yellow setae), black part with posteriorly directed, black, decumbent pubescence (apical third mixed with some light yellow setae as well).

Diagnosis.
Differs from T. hirsuta by absence of tubercular rows on basal elytral intervals, elytral apex not emarginate; from T. michaeli by absence of tuberosity on elytral base (on third interval exactly) and absence of tubercular rows on basal elytral intervals, integument from which two bands of golden setae originate yellow, elytra apex not projecting nor acute, color of first three antennomeres light paler, legs black. Thanasimus hirsuta Pic, 1926: 22 (Tonkin). Tillicera hirsuta: Gerstmeier & Bernhard, 2010: 18. Diagnosis. Differs from T. bibalteata by having tubercular rows on basal elytral intervals, elytral apex emarginate; from T. michaeli by absence of tuberosity on elytral base (on third interval exactly), diameter of interstitial tubercules larger than diameter of punctures on elytra, integument from which two bands of golden setae originates yellow, elytral apex emarginate, first four antennomeres paler.  Pic, 1926= Tillicera hirsuta, Revision 2009.
Remarks. The name-bearing type was not fixed in the original publication and there was no imply how many type series was. For the purpose to fix the name-bearing type, the lectotype is designated here, which is the same specimen noted as "holotype" in Gerstmeier & Bernhard (2010).
Diagnosis. Differs from T. bibalteata by having a tuberosity on elytral base (on third interval exactly), each basal elytral interval with a row of tubercules, integument from which two bands of golden setae originate black, elytra apex slightly projecting and acute, color of first three antennomeres black, legs reddish brown; from T. hirsuta by having a tuberosity in basediscal elytra (on third interval exactly), diameter of interstitial tubercules smaller than diameter of punctures on elytra, integument from which two bands of golden setae originate black, elytral apex slightly projecting and acute, first four antennomeres black.  Gerstmeier & Bernhard, 2009 Revision, Gerstmeier & Bernhard" (RGCM); Paratype: 2 specimens, same locality data as Holotype; 1 specimen, same data but 28. VII.2006 (RGCM).

Discussion
The placement of the species T. wenii sp. n. into the genus Tillicera might receive some controversy, because currently the most important character of the genus Tillicera is tarsal pulvillar formula 4-4-2 (Gerstmeier 2002(Gerstmeier , 2006Gerstmeier and Bernhard 2010;Opitz 2010), while the tarsal pulvillar formula of T. wenii is 4-4-4. But note that none of other species of genera related to Clerus and Tillicera (sensu Gerstmeier 2010) shows 4-4-4 tarsal pulvillar formula, and the general appearance, male phallus (phallic plate with large denticles along dorsal margin and fine granular structures on posterior sclerotized area) and presence of pit-like sensilla on male terminal antennomere suggest a close relationship among T. wenii and T. auratofasciata and T. sensibilis, and its recent relatives might as well include T. soror (from Bhutan) and T. javana (from Java) based on their aedeagi illustrated by Gerstmeier and Bernhard (2010). "It is the genus that pronounces the characters, and not the characters that pronounces the genus" (Linnaeus 1737;Mayr 1969;Opitz 2010). T. wenii might be a special and advanced species in the lineage of that includes T. auratofasciata, T. sensibilis, T. soror and T. javana.
The extreme close relationship between T. auratofasciata and T. sensibilis can be additionally inferred from the characters below (unfortunately the female of T. wenii is unknown): female vagina swollen, base of bursa copulatrix narrower than posterior end of vagina, length of bursa copulatrix three times as long as spermatheca, spermathecal gland attached to basal fourth of spermatheca; the male phallic posterior scleroitzed area of both sharply reduced in size, both have the ventral membrane with one line of file-like structures on each side, the pit-like sensillum on each terminal antennomere of males larger, shallower and straight.
T. bibalteata and T. hirsuta appear to be closely related; the evidence being that they have the same type of male phallus and female internal reproductive organs (phallic plate with small denticles on both dorsal and ventral margins; base of bursa copulatrix as wide as posterior end of vagina; length of bursa copulatrix is at least four times as long as spermatheca) (45)(46).
The positions of T. cleroides and T. michaeli are uncertain. Phallus and female internal reproductive organs of T. cleroides do not provide evidence of its relationship to other species (the phallic plate with small denticles along dorsal ventral margin and larger denticles on the ventral margin, base of bursa copulatrix as wide as posterior end of vagina, and spermathecal gland attached to the middle of spermatheca) (Figs 44, 48), but its pronotum indeed gives a very different look among this genus (Fig. 3). As for T. michaeli, its phallic plate is uniformly sclerotized near the apex and without marginal denticles (Fig. 43), and the integument from which the two bands of golden setae originate is not yellow but black, which might indicate a close relationship to some species of Clerus than to other species of Tillicera.
Whether the current genus Tillicera is a monophyly might need further examination, because firstly the characters to support this genus currently (antennomeres triangularly dilated from the fifth and tarsal pulvillar formula 4-4-2) are not adequate; some species currently placed in Tillicera do not exhibit the typical triangularly dilated antennomeres and some Chinese related species not placed in Tillicera at present show 4-4-2 pulvillar formula as well. Secondly, as discussed in the above paragraph, some species currently placed in Tillicera might be closer to some species of Clerus than to other species of Tillicera. Actually, this is a problem of the generic definition of Clerus-Tillicera group, rather a problem of merely Tillicera. It is clear that a sound definition of the Clerus-Tillicera group, based on a greater range of characters (especially external and internal reproductive organs) is required, though this may not be accomplishable before all the representative species of this group are taxonomically revised. Conversely, the systematic importance of the pulvillar formula in Clerus-Tillicera group (especially for those with 4-3-2, 4-4-2 tarsal pulvillar formula) might require further test and the true systematic value of the pulvillar formula, however, may be better realized if these structures were more carefully considered in terms of the degree of development of each pulvillus rather than just a formula (eg. distinctly or feebly lobed apically, or present but unlobed or vestigeal).
The pit-like sensillum of the male terminal antennomere was discovered during the course of the present study, and we found this structure in some undetermined Chinese Cleridae as well. Whether this sexually correlated character can provide additional evidence to infer a close relationship between species-groups might require further investigation.